1. Field of the Invention
The present invention relates to a silver halide photographic light-sensitive material, and more particularly, to a silver halide photographic light-sensitive material containing a developing agent.
2. Description of the Related Art
A photographic method using silver halide has conventionally been most widely used since it has more excellent photographic characteristics such as sensitivity, gradation control and the like as compared with other photographic methods, for example, an electrophotographic method and diazo photographic method. Further, the photographic method using silver halide has been intensively studied nowadays since it can provide the maximum image quality as a color hard copy.
Recently, a method for image forming treatment of a light-sensitive material using silver halide including conventional wet treatment has been improved, and consequently, an instant photographic system containing a developing solution therein and further a system which can obtain an image simply and rapidly using dry heat developing treatment and the like by heating and the like have been developed. In particular, a heat developing light-sensitive material is described in "Base for Photographic Technology (ed. by Non-Silver Salt Photography, Corona Corp.)", p. 242, and the contents thereof only refer to a black-and-white image forming method typically represented by dry silver. Recently, as a heat developing color light-sensitive material, products such as Pictography and Pictostat are commercially available from Fuji Photo Film Co., Ltd. In the above-described simple and rapid treatment method, there is effected color image formation using a redox-type coloring material to which a preformed dye has been bonded.
As a method for color image formation of a photographic light-sensitive material, a method utilizing a coupling reaction of a coupler with a developing agent oxidation product is most general, and with respect to an idea of a heat developing color light-sensitive material according to this method, there are a lot of applications such as U.S. Pat. Nos. 3,761,270, 4,021,240, Japanese Patent Application Laid-Open (JP-A) Nos. 59-231539, 60-128438 and the like.
When a silver halide photographic light-sensitive material capable of being treated simply and rapidly as described above is designed, a treating solution including a developing solution is not used. Therefore, it is essential that the light-sensitive material contains a developing agent. Usually, the developing agent is a reducing agent. Therefore, a general developing agent is a compound which is easily oxidized by an oxygen molecule in air. Such a compound can not effectively be used for the above-described treatment. To solve this problem, there have been proposed many ideas such as methods for solid dispersion addition of p-sulfoneamidephenol described in U.S. Pat. No. 4,021,240, p-aminophenylsulfamic acid described in JP-A No. 60-128439, sulfonylhydrazine described in JP-A No. 8-227131, sulfonylhydrazone described in JP-A No. 8-202002, carbamoylhydrazine described in EP No. 0727708A1, carbamoylhydrazine described in JP-A No. 8-234390, and 1-phenyl-3-pyrazolidinone derivative described in JP-A No. 2-230143, as a developing agent which can be contained in the light-sensitive material, in the present field.
The inventors of the present invention have studied the silver halide photographic light-sensitive material containing a developing agent. As a result, they have found that when a p-aminophenol derivative and p-phenylenediamine derivative are used as a developing agent, a dye which can manifest excellent hue can be formed, with combination of a coupler used in the art. Particularly, they have found that sulfoneamidephenol described in U.S. Pat. No. 4,021,240, JP-A No. 60-128438 and the like is a compound excellent in discrimination and storage when it is used in a light-sensitive material.
However, they also have found that p-sulfoneamidephenol manifests extremely low color developing efficiency when it is combined with a so-called 2-equivalent coupler which is usually used in the art. The reason is that the coupling site of this compound is substituted with a sulfonyl group, and this sulfonyl group releases in the form of a sulfinic acid at the time of coupling reaction, therefore, a releasing group on the coupler side has to release in the form of a cation. Therefore, this compound reacts with a 4-equivalent coupler which can release a proton as a releasing group and develops color at the time of the coupling reaction. However, in the case of a 2-equivalent coupler, of which the releasing group is an anion, it is very difficult to effect color development, though reaction itself does occur.
Because reaction with a 2-equivalent coupler is difficult, when a developing agent like p-sulfoneamidephenol is used, it is difficult to construct a system in which a diffusive dye is formed by releasing a functional compound from the coupling site of a coupler, by substituting a ballasting group onto the coupling site and releasing the ballasting group, and the like. Further, the 4-equivalent coupler is known to have a problem also in formalin gas resistance. Therefore, the present inventors have investigated means by which a developing agent using aminophenol type and phenylenediamine type developing agents having a releasing group at the coupling site as described above can cause a color developing reaction efficiently with a 2-equivalent coupler.